During this study, more than 300 people with these complaints were followed for 5 years. For example, it has been mapped out how the complaints develop and which mechanisms underlie this. Just to be clear right away, ALK is the same as the commonly heard term MUS, or Somatically Insufficiently Explained Physical Complaints. “The people who suffer from these kinds of complaints often do not feel represented by the term MUS,” explains Hieke Barends, PhD student and general practitioner in training at Amsterdam UMC, about the choice of the term ALK in the PROSPECTS study.
These Persistent Physical Complaints, such as pain or fatigue, sometimes go away on their own. In other cases, patients have long-term complaints. These can range from mild to severe. Sometimes patients are even unable to work. Patients also often visit several doctors without receiving a diagnosis and/or treatment. ALK therefore has a major personal and social impact, which makes research into it very important. Barends: “It is important that we learn more about this, so that doctors know better how they can help someone further.”
Run long term
The PROSPECTS study focused on the long-term course of the complaints, something we knew little about. People with complaints were followed for 5 years to chart the course of the complaints and to find out which factors are associated with this. With the help of questionnaires, the more than 300 participants regularly gave an impression of their physical and mental health and the perceived severity of their complaints. Some of the participants came through their general practitioner, others from specialized treatment centres.
“Based on previous research, we thought that 50 to 75 percent of people with ALK would recover, and that the complaints would become chronic in 10 to 30 percent of people,” says Barends. But now that people have been followed longer and asked how they were doing at more times, a different picture has emerged. “We already saw in the 2-year measurement that the complaints are very erratic, people have ups and downs. But over a period of 5 years, these more often indicate a chronic course. This is evident in no less than 70 percent of the participants the case.”
Mechanisms at the origin of complaints
The study had been running for 2 years when Hieke Barends joined the project as a principal investigator and PhD student at the department of general practice at Amsterdam UMC, location VUmc and Amsterdam Public Health research institute. After several years as an emergency room doctor, she now specializes as a general practitioner. She used the data from the research to investigate 3 common models for the persistence of unexplained complaints. These models form the basis of treatments, but have hardly been scientifically investigated.
One such model is the somatosensory amplification theory. This assumes that complaints increase when people pay more attention to them. The data does indeed show that this mechanism plays a role in the increase in complaints. Barends also looked at the role of traumatic life events, which are already known to lead to a higher risk of ALK.
Influence of traumatic events
This effect appeared to differ within the group of participants in the study. “We saw that childhood traumas in particular matter, recent traumas in themselves have less effect,” says Barends. “The combination of trauma in early childhood and later in life can cause an accumulation, which increases the chance of a more serious course of the persistent physical complaints.”
Finally, Barends looked at the influence of negative thoughts and behaviour. The data showed that these had an influence on the degree of experienced complaints and associated limitations. In addition, these factors seem to influence each other mutually. “More serious complaints and less functioning lead to more negative thoughts. This confirms the idea that these types of circular processes can play a role in maintaining ALK,” Barends explains.
By: National Care Guide